STUDY ON PROCESS PARAMETERS IN METALLOCENE POLYMERIZATIONS .2. HEAT-TRANSFER AND COPOLYMER COMPOSITION

Part I of this series about the determination of the typical process p arameters in Et[Ind]2ZrCl2-methylaluminoxane-catalyzed polymerizations carried out with a heat balance reaction calorimeter described how vi scosity and macro-scale mass transfer characteristics changed during t he polymerization. Part II looks at the heat transfer properties and t he copolymer compositions. The dimensionless Nusselt equation was used to calculate the reaction-side heat transfer coefficient during the p olymerization. The properties of the reaction mixture changed continuo usly during the polymerization, which means that the dimensionless Nus selt equation needs to be modified to properly express the heat transf er properties. The copolymer compositions were estimated by combining the calorimetric method with the semibatch ethylene polymerization met hod. Results gathered in this way were reliable when the amount of com onomer in the copolymer exceeded 5 mol-%.